PROJECT SUMMARY/ABSTRACT The goal of the current project is to assess the efficacy of Central Executive Training (CET) for youth with ADHD. Consistent with NIMH Strategic Objective #3 and the NIH (1998) Consensus Statement on ADHD, our R34 developed CET to translate clinical neurocognitive findings into a novel clinical protocol that affects ADHD behavioral symptoms by targeting central processes. The final, computerized CET protocol reflects the contributions and feedback of a diverse group of caregivers, children with ADHD, and recognized experts in human cognition, ADHD treatment research, RCT intervention design methods, serious game theory and task design, cognitive training, and the role of executive dysfunction in ADHD. Pilot data suggest considerable promise for improving working memory and ADHD symptoms among youth with ADHD. The current project will provide a rigorous test of CET relative to an active, credible comparator (ACC). ACC was also developed during the R34, and is identical to CET in all regards except the proposed mechanism of action (training central executive working memory).